Small retrospective studies have shown isotretinoin to be effective in reducing the rate of recurrent retinal detachment in patients with or at high risk for developing PVR. This is a prospective study to evaluate a low dose of oral isotretinoin in this regard. There are two arms to the study: 1) eyes with recurrent retinal detachment due to existing PVR, and 2) eyes with primary detachment and features associated with a high risk of PVR formation. Eligible and willing patients will receive a 12-week course of isotretinoin, and will be followed for retinal attachment rate, and PVR and/or ERM (epiretinal membrane) formation.